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41.
Multiplex ligation-dependent probe amplification (MLPA) is a new assay for the detection of multiple chromosomal deletions in tumor tissue in a single experiment. Since genotyping of gliomas with oligodendroglial features by the detection of 1p/19q chromosomal deletions became essential for treatment decisions, we developed and validated an MLPA-based assay to determine these losses in formalin fixed and paraffin embedded oligodendroglial tumors (OG). Nineteen OGs, and 10 control samples were analyzed by MLPA and the results were correlated with those obtained by fluorescent in situ hybridization (FISH). The MLPA results were reproducible in all samples in which repeated experiments were performed. In 18 of 19 OGs, MLPA and FISH were concordant for presence or absence of 1p deletion. In 3 OGs, MLPA detected a 19q deletion not shown by FISH. For the other 15 OGs, MLPA and FISH were concordant. In one sample with 50% to 75% of tumor, MLPA failed to detect the 1p/19q deletions revealed by FISH (though with borderline values of significance). We conclude that MLPA is a valid and reproducible method for the detection of 1p/19q chromosomal deletions in OGs stored on formalin fixed, paraffin embedded tissue.  相似文献   
42.

Background

Routine Outcome Monitoring (ROM) is a systematic way of assessing service users’ health conditions for the purpose of better aiding their care. ROM consists of various measures used to assess a service user’s physical, psychological, and social condition. While ROM is becoming increasingly important in the mental health care sector, one of its weaknesses is that ROM is not always sufficiently service user-oriented. First, clinicians tend to concentrate on those ROM results that provide information about clinical symptoms and functioning, whereas it has been suggested that a service user-oriented approach needs to focus on personal recovery. Second, service users have limited access to ROM results and they are often not equipped to interpret them. These problems need to be addressed, as access to resources and the opportunity to share decision making has been indicated as a prerequisite for service users to become a more equal partner in communication with their clinicians. Furthermore, shared decision making has been shown to improve the therapeutic alliance and to lead to better care.

Objective

Our aim is to build a web-based support system which makes ROM results more accessible to service users and to provide them with more concrete and personalized information about their functioning (ie, symptoms, housing, social contacts) that they can use to discuss treatment options with their clinician. In this study, we will report on the usability of the web-based support system for service users with schizophrenia.

Methods

First, we developed a prototype of a web-based support system in a multidisciplinary project team, including end-users. We then conducted a usability study of the support system consisting of (1) a heuristic evaluation, (2) a qualitative evaluation and (3) a quantitative evaluation.

Results

Fifteen service users with a schizophrenia diagnosis and four information and communication technology (ICT) experts participated in the study. The results show that people with a schizophrenia diagnosis were able to use the support system easily. Furthermore, the content of the advice generated by the support system was considered meaningful and supportive.

Conclusions

This study shows that the support system prototype has valuable potential to improve the ROM practice and it is worthwhile to further develop it into a more mature system. Furthermore, the results add to prior research into web applications for people with psychotic disorders, in that it shows that this group of end users can work with web-based and computer-based systems, despite the cognitive problems they experience.  相似文献   
43.
Human Papilloma Virus (HPV)-induced (pre-)malignancies offer an excellent case for the rational design of immunotherapeutic strategies against cancer. Transformed cells express tumor-specific antigens of viral origin while the spontaneous antitumor response and the immunological make up of HPV-induced tumors do not differ from other immunogenic epithelial tumors. A first clinically active therapeutic HPV vaccine has been developed and clear links were found between the type and kinetics of vaccine-induced T-cell immunity. Here, we will review the mechanisms determining the success and failure of therapeutic vaccines against HPV-induced tumors, with particular emphasis on the immunological setting in which these vaccines need to work. The recent progress in therapeutic HPV vaccination will guide the development of successful vaccines in other diseases.  相似文献   
44.
A large number of mutations in the gene encoding the catalytic subunit of mitochondrial DNA polymerase γ (POLγA) cause human disease. The Y955C mutation is common and leads to a dominant disease with progressive external ophthalmoplegia and other symptoms. The biochemical effect of the Y955C mutation has been extensively studied and it has been reported to lower enzyme processivity due to decreased capacity to utilize dNTPs. However, it is unclear why this biochemical defect leads to a dominant disease. Consistent with previous reports, we show here that the POLγA:Y955C enzyme only synthesizes short DNA products at dNTP concentrations that are sufficient for proper function of wild-type POLγA. In addition, we find that this phenotype is overcome by increasing the dNTP concentration, e.g. dATP. At low dATP concentrations, the POLγA:Y955C enzyme stalls at dATP insertion sites and instead enters a polymerase/exonuclease idling mode. The POLγA:Y955C enzyme will compete with wild-type POLγA for primer utilization, and this will result in a heterogeneous population of short and long DNA replication products. In addition, there is a possibility that POLγA:Y955C is recruited to nicks of mtDNA and there enters an idling mode preventing ligation. Our results provide a novel explanation for the dominant mtDNA replication phenotypes seen in patients harboring the Y955C mutation, including the existence of site-specific stalling. Our data may also explain why mutations that disturb dATP pools can be especially deleterious for mtDNA synthesis.  相似文献   
45.
BACKGROUND: The aim of this study was to compare morbidity and mortality of patients who had epidural analgesia for at least 2 days after transthoracic esophagectomy for cancer with those who did not have epidural analgesia at all or who had it for less than 2 days. STUDY DESIGN: We analyzed 182 patients, 7 of whom were excluded. Patients were divided into two groups; 90 patients (51%) with epidural analgesia for at least 2 days (epidural group) and 85 patients (49%) who did not have epidural analgesia or had it for less than 2 days (no epidural group). To identify prognostic factors for pneumonia, univariate and multivariate logistic regression analyses were performed. RESULTS: There were no notable differences in clinicopathologic characteristics or intraoperative measurements. In favor of the epidural group, marked differences were found in pneumonia (28% versus 48%, p = 0.005), reintubation (17% versus 34%, p = 0.011), ICU-stay (median 2.8 versus 5.8 days, p = 0.001), hospital stay (median 17 versus 21 days, p = 0.015), and in-hospital mortality (0 versus 8 patients, p = 0.003). No epidural analgesia (odds ratio [OR] 2.48, 95% CI 1.30 to 4.71, p = 0.006) and atelectasis (OR 2.06, 95% CI 1.08 to 3.90, p = 0.028) were independent predictors for pneumonia. There were eight in-hospital deaths. CONCLUSIONS: No epidural analgesia for more than 2 days after a transthoracic esophageal cancer resection is associated with increased postoperative morbidity. To optimize postoperative recovery, it is of vital importance to ensure adequate epidural analgesia in these patients.  相似文献   
46.

Background and Study Aim

Obstructive sleep apnea (OSA) occurs in 70–80 % of bariatric surgery patients. Patients with severe OSA (apnea/hypopnea index (AHI) >30/h) are postoperatively admitted to an intensive care unit (ICU) for continuous monitoring, to prevent complications. The aim of this study was to assess the necessity of routine postoperative monitoring at an ICU of severe OSA patients after bariatric surgery, attempting to prevent and detect cardiorespiratory complications.

Methods

Patients undergoing bariatric surgery from November 2010 to July 2013 were entered into a database. Minimal follow-up was 1 month. Poly(somno)graphy (P(S)G) was routinely performed. Patients with severe OSA were admitted to the ICU for the first postoperative night. Oxygen saturation was continuously measured. The database was reviewed regarding patient characteristics, CPAP use, re-intubations, desaturations (saturation <90 % and severe <85 %), and complications.

Results

Severe OSA was present in 151 of the 794 patients, and all 151 were admitted to the ICU. Thirty who underwent revisional surgery were excluded. Forty-seven percent was male, median age was 51 years (27.0–68.0), and median body mass index (BMI) was 46.6 (kg/m2) (34.0–77.6). No deaths, re-intubations, or cardiopulmonary complications occurred. Eighty-two (67.8 %) patients used continuous positive airway pressure (CPAP). Twenty-one (17.4 %) patients experienced desaturations with a median of 2.0 (1–8). Six patients (5.0 %) had one episode of severe desaturation.

Conclusion

Patients with severe OSA and adequate CPAP use are at low risk of cardiopulmonary complications after (laparoscopic) bariatric surgery. Routine admission to an ICU might be superfluous. However, continuous digital oximetry remains essential.
  相似文献   
47.
48.

Objective

To validate the application of an automated neuronal spike classification algorithm, Wave_clus (WC), on interictal epileptiform discharges (IED) obtained from human intracranial EEG (icEEG) data.

Method

Five 10-min segments of icEEG recorded in 5 patients were used. WC and three expert EEG reviewers independently classified one hundred IED events into IED classes or non-IEDs. First, we determined whether WC-human agreement variability falls within inter-reviewer agreement variability by calculating the variation of information for each classifier pair and quantifying the overlap between all WC-reviewer and all reviewer-reviewer pairs. Second, we compared WC and EEG reviewers’ spike identification and individual spike class labels visually and quantitatively.

Results

The overlap between all WC-human pairs and all human pairs was >80% for 3/5 patients and >58% for the other 2 patients demonstrating WC falling within inter-human variation. The average sensitivity of spike marking for WC was 91% and >87% for all three EEG reviewers. Finally, there was a strong visual and quantitative similarity between WC and EEG reviewers.

Conclusions

WC performance is indistinguishable to that of EEG reviewers’ suggesting it could be a valid clinical tool for the assessment of IEDs.

Significance

WC can be used to provide quantitative analysis of epileptic spikes.  相似文献   
49.
Joint arthroplasty registries show an increased rate of aseptic loosening in uncemented acetabular components as compared to cemented acetabular components. Since loosening is associated with particulate wear debris, we postulated that uncemented acetabular components demonstrate a higher polyethylene wear rate than cemented acetabular components in total hip arthroplasty. We performed a systematic review of the peer-reviewed literature, comparing the wear rate in uncemented and cemented acetabular components in total hip arthroplasty. Studies were identified using MEDLINE (PubMed), EMBASE and the Cochrane Central Register of Controlled Trials. Study quality was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The search resulted in 425 papers. After excluding duplicates and selection based on title and abstracts, nine studies were found eligible for further analysis: two randomised controlled trials, and seven observational studies. One randomised controlled trial found a higher polyethylene wear rate in uncemented acetabular components, while the other found no differences. Three out of seven observational studies showed a higher polyethylene wear in uncemented acetabular component fixation; the other four studies did not show any differences in wear rates. The available evidence suggests that a higher annual wear rate may be encountered in uncemented acetabular components as compared to cemented components.  相似文献   
50.

Background

If all initially node-positive patients undergo axillary lymph node dissection (ALND) after neoadjuvant chemotherapy (NAC), overtreatment may occur in patients with complete response. Positron emission tomography–computed tomography (PET/CT) during NAC may predict axillary response and select patients appropriate for less invasive treatment after NAC. We evaluated the value of sequential 18F fluorodeoxyglucose (FDG) PET/CTs during NAC for axillary response monitoring in stage II–III breast cancer.

Methods

A total of 219 PET/CTs were performed in 80 patients with cytology-proven, node-positive disease at baseline (PET/CT1, n = 80) and twice during NAC (PET/CT2 n = 62, PET/CT3, n = 77). The relative changes in maximum standardized uptake value (SUVmax) of axillary nodes were examined for their ability to assess pathological response. All patients underwent ALND after chemotherapy, and complete axillary response (pCR), defined as absence of isolated tumor cells and of micro- and macrometastases, served as the reference standard.

Results

A total of 32 (40 %) patients experienced axillary pCR. The relative decrease in SUVmax was significantly higher in patients with pCR than in those without, both on PET/CT2 (p < 0.001) and PET/CT3 (p = 0.025). The area under the receiver operating characteristic curve values for PET/CT2 and PET/CT3 were 0.80 (95 % confidence interval 0.68–0.92) and 0.65 (95 % confidence interval 0.52–0.79), respectively. A relative decrease of ≥60 % on PET/CT2 had an excellent specificity (35 of 37, 95 %), a high positive predictive value (12 of 14, 86 %), and a sensitivity of 48 %—that is, it accurately identified histologic pCR in 12 of 25 patients with disease that responded to therapy.

Conclusions

18F-FDG PET/CT early during NAC is useful for axillary response monitoring in cytology-proven node-positive breast cancer because it identifies pathological response, thus permitting ALND to be spared.  相似文献   
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